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A ir-sea/land interaction: physics and observation of planetary boundary layers and quality of environment Mega-Grant, started November 1 st 2011 University of Nizhny Novgorod, Russia INSTITUTIONS-COLLABORATORS

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Air-sea/land interaction: physics and observation of planetary boundary layers and quality of environment

Mega-Grant, started November 1st 2011

University of Nizhny Novgorod, Russia


Institute of Applied Physics RAS; Faculty of Geography of Moscow State University; Russian State Hydrometeorological University; A.M. Obukhov Institute of Atmospheric Physics RAS – RUSSIA // Danish Meteorological Institute – DENMARK // Finnish Meteorological Institute; Dept of Physics of University of Helsinki – Finland // Ben-Gurion University of the Negev – ISRAEL // Nansen Environmental and Remote Sensing Centre – NORWAY…


Mega-grants for environmental challenges 24-26.05.2012


and content

Geophysical turbulence and planetary boundary layers pbls
Geophysical turbulence and planetary boundary layers (PBLs)



New concepts of random

and self-organised motions

in geophysical turbulence

PBLs link atmosphere,

hydrosphere, lithosphere

and cryosphere within

weather & climate systems

Revision of basic theory

of turbulence and PBLs

Improved “linking algorithms”

in weather & climate models

Progress in understanding and modelling

weather & climate systems

Geospheres in climate system
Geospheres in climate system

Atmosphere, hydrosphere, lithosphere and cryosphere are coupled through turbulent planetary boundary layers PBLs (dark green lenses)

PBLs include 90% biosphere and entire anthroposphere

Role of planetary boundary layers pbls traditional view
Role of planetary boundary layers (PBLs): TRADITIONAL VIEW

“Surface fluxes” through



WATER (or LAND) interfaces

fully characterise interaction between




Monin-Obukhov similarity theory (1954) (conventional framework for determining surface fluxes in operational models) disregards non-local features of both convective and long-lived stable PBLs

Role of pbls modern view

Because of very stable stratification in the atmosphere and ocean beyond the PBLs and convective zones, strong density increments inherent in the PBL outer boundaries prevent entities delivered by surface fluxes or anthropogenic emissions to efficiently penetrate from the PBL into the free atmosphere or deep ocean.

Hence the PBL heights and the fluxes due to entrainment at the PBL outer boundaries essentially control extreme weather events (e.g., heat waves associated with convection; or strongly stable stratification events triggering air pollution).

This concept (equally relevant to the hydrosphere) brings forth the problem of determining the PBL depth and the turbulent entrainment in numerical weather prediction, air/water quality and climate modelling.




Ocean PBL


Very shallow boundary layer separated form the free atmosphere by capping inversion
Very shallow boundary layer separated form the free atmosphere by capping inversion

PBL height visualised by smoke blanket (Johan The Ghost, Wikipedia)

Pbl height and air quality
PBL height and air quality atmosphere by capping inversion

Tasks atmosphere by capping inversion

Geophysical turbulence and PBLs Non-local nature  Revision of traditional theory  Improved practical applications (SZ)

Atmospheric electricity Convective PBLs, thunderstorms, upper atmosphere  role in global electric circuit  applications (EM)

Air-sea interaction Processes at air-sea interface (theory, lab and field experiments)  application to hurricanes, storms (YuT)

Internal waves Interaction with turbulence, wave-driven transports (ocean, ionosphere)  role in climate machine (AK)

Chemical weather / climate Fires and modelling air pollution  troposphere and middle atmosphere (AF)

New methods of radio-physical observations Instruments to respond new challenges  turbulence, organised structures, chemical composition  commercialisation (AF, AU)

Education and young-scientist programme  new PhD, Dr.Sci.

Pbl and turbulence problems
PBL and turbulence problems atmosphere by capping inversion

Self-organisation of turbulent convection Failure of the MO similarity theory  non-local resistance and heat/mass transfer laws (free and forced convection regimes); growth rate of and turbulent entrainment into convective PBLs

Non-local nature of stably stratified PBLs ”Long-lived stable” and “conventionally neutral” very shallow and therefore sensitive (typical of Polar areas and over ocean); diagnostic and prognostic PBL-height equations

Dead locks in and new concept of turbulence closure Potential energy, self-preservation of stably stratified turbulence  no critical Richardson number; new “weak turbulence” regime with diminishing heat transfer (everywhere in the atmosphere and hydrosphere beyond PBLs and convective zones)

Turbulent convection

Cloud streets visualising updraughts in convective rolls atmosphere by capping inversion

Photo J. Gratz

Turbulent convection

LES I. Esau

In the atmosphere


Development of convective clouds self organised cells in the atmosphere
Development atmosphere by capping inversion of convective cloudsSelf-organised cells in the atmosphere

Гора Леммон, Аризона

Cloud systems over north polar ocean
Cloud systems over atmosphere by capping inversionNorth Polar Ocean

Convective cells

Weak wind

 free convection‏

Convective rolls

Strong wind

 forced convection

Self organisation
Self-organisation atmosphere by capping inversion

Self-organisation in viscous convection isknown since

Benard (1900) and Rayleigh (1916)

It is obviously presents in turbulent convection but missed in essentially local classical theories:

  • Heat and mass transfer law Nu ~ Ra1/3

  • Prandtl theory of free convectionWc= (βFsz)1/3

  • Monin-Obukhov similarity theory L= τ3/2 (βFs)-1

    and in all parameterizations based on these theories

    Revision of the theory is demanded

Non local theory of convective heat and mass transfer

Example of solved problem atmosphere by capping inversion

Non-local theory of convective heat and mass transfer

Organised cell in turbulent convection disregarded in classical theory
Organised cell in turbulent convection atmosphere by capping inversion(disregarded in classical theory)

Air-borne measurements, calm sunny day over Australian desert: arrows – winds; lines – temperatures (Williams and Hacker, 1992)

Heat and mass transfer in free convection non local theory
Heat and mass transfer in free convection: atmosphere by capping inversionnon-local theory


Convective wind pattern includes the convergence flow towards the plume axes at the surface

Near-surface internal boundary layer

”minimum friction velocity U*(Businger,1973)

Strongly enhanced heat/mass transfer

Heat transfer coefficient
Heat-transfer coefficient atmosphere by capping inversion

Blue symbols observations

Red symbolsLES


Classical theory (Nu = C0Ra1/3)

disregards dependence onh/z0

and underestimates heat transfer over rough surfaces up to 2 orders of magnitude

Convective heat mass transfer conclusions
Convective heat/mass transfer: conclusions atmosphere by capping inversion

Classical (local) theory disregards self-organisation of turbulent convection and strongly underestimates heat/mass transfer in nature

Developed Non-local theory of free convection(cells, weak winds) Essential dependence of heat/mass transfer on the ratio of boundary-layer depth to roughness length (h/z0u)New turbulent entrainment equation accounting for IGW mechanism

Under development  Non-local theory of forced convection (rolls at strong winds)

Applications to modelling air flows over warm pool area in Tropical Ocean (free convection / known)  openings in Polar ocean (forced convection / prospective)  urban heat islands, deserts, etc. (prospective

Convection principal statement

2 atmosphere by capping inversionh

Convection: principal statement

Convective structures are supplied with energy through inverse energy cascade(from smaller to larger eddies). They resemble secondary circulations rather then large turbulent eddies

Cloud streets visualising convective rolls stretched along the strong wind (Queensland, North Coast, Australia, Wikimedia Commons; photo by Mick Petroff)

In both figures h ~ 103мis the height of convective layer

Vertical cross-section of a convective cell at weak wind over Australian desert (airborne observations by Williams and Hacker, 1992)

Turbulence in stable stratification
turbulence atmosphere by capping inversionin stable stratification

Very shallow long-lived stable boundary layer over cold Lake Teletskoe (Altay, Russia) on 28 August 2010 (photo by S. Zilitinkevich). Smoke blanket visualises upper boundary of the layer

Non local theory of long lived stably stratified planetary boundary layers pbl s

Example of solved problem atmosphere by capping inversion

Non-local theory of long-lived stably-stratified Planetary boundary layers(PBLs)

S. Galmarini, JRC

Stable and neutral pbls
Stable and neutral PBLs atmosphere by capping inversion

Traditional theory (adequate over land at mid latitudes)

  • is valid in the presence of pronounced diurnal course of temperature

  • recogniseed only two types of stably or neutrally stratified PBL, REGARDLESS STATIC STABILITY AT PBL OUTER BOUNDARY:

    stable (factually nocturnal stable– capped by residual layer)

    neutral (factually truly neutral– capped by residual layer)

    Non-local theory (2000-2010)

  • accounted for the free flow-PBL interaction through IGW or structures

  • led to discovery of additional types of PBL:

    long-lived stable(50 % at high latitudes)

    conventionally neutral(40 % over ocean)

  • both proved to be much shallower than mid-latitudinal PBLs

Temperature stratification in a nocturnal and b long lived stable pbls
Temperature stratification in (a) nocturnal and (b) long-lived stable PBLs

The effect of the free flow stability on the pbl height
The effect of the free flow stability (a) nocturnal and (b) long-lived stable PBLson the PBL height


● observations

Traditional (local) theory

New non-local theory (Z et al., 2007)‏





Polar PBL

Stable pbls conclusions
Stable PBLs: Conclusions (a) nocturnal and (b) long-lived stable PBLs

Non-local nature

due to long-lived structures and/or internal waves

Triggering air pollution

the shallower PBL  the heavier air pollution

Sensitivity to thermal impacts

the shallower PBL  the stronger microclimate response

 triggering global warming in stable PBLs:

in winter- and night-time at Polar and high latitudes

Features of scientific revolution tomas kun structure of scientific revolutions 1962
Features of ”scientific revolution” (a) nocturnal and (b) long-lived stable PBLs(Tomas Kun, Structure of scientific revolutions, 1962‏)


Forward cascade

Fluid flow =mean (regular) +turbulence (chaotic)

Applicable to neutrally- and weakly-stratified flows

Crises of traditional theoryALTERNATIVE PARADIGM

Forward(randomisation) and inverse (self-organisation) cascades

Fluid flow =mean (regular) +Kolmogorov’sturbulence (chaotic)

+anarchic turbulence (with inverse cascade)

+organised structures (regular)


Self-organisation of turbulent convection

Structures and internal waves in stable PBLs

Non-local closures Much work to be doneNumerous simple unsolved problems



Towards ”scientific revolution” (a) nocturnal and (b) long-lived stable PBLsMarie Curie Chair – PBL (2004-07); ERC-IDEAS PBL-PMES (2009-13); RU-Gov. Mega-Grant – PBL (2011-13)

Co-authors from > 30 groups / 15 countries

Finland(FMI, U-Helsinki); Russia((Nizhny Novgorod State Univ., Obukhov Inst. Atmos. Phys., Rus. State Hydro-met. Univ.)

Sweden(MIUU, MISU, SMHI); Norway (NERSC-Bergen);

Denmark (RISOE National Lab, DMI-Copenhagen); Israel (Ben-Gurion Univ., Weizmann Inst. Advance Studies);

UK (Univ. College London, Brit. Antarctic Sur. Cambridge);

USA (Arizona State Univ., Univ. Notre Dame, NCAR, NOAA); Brazil(UNIPAMA, Univ.-Rio Grande, Univ.-Santa Maria); Greece (Nat. Obs., Univ.-Athens); Germany (Univ.-Freiburg); Estonia (Tech. Univ.-Tallinn); Switzerland (SFIT, EPF-Lausanne);

France (Univ.-Nantes); Croatia (Univ.-Zagreb)

Thank you (a) nocturnal and (b) long-lived stable PBLs

for your attention